The SpaceX Draco is a hypergolic liquid

rocket engine A rocket engine uses stored rocket propellants as the reaction mass for forming a high-speed propulsive jet of fluid, usually high-temperature gas. Rocket engines are reaction engines, producing thrust by ejecting mass rearward, in accorda ...

designed and built by SpaceX for use in their space capsules. Two engine types have been built to date: Draco and SuperDraco. The original Draco thruster is a small rocket engine for use on the Dragon spacecraft.

SuperDraco SuperDraco is a hypergolic propellant rocket engine designed and built by SpaceX. It is part of the SpaceX Draco family of rocket engines. A redundant array of eight SuperDraco engines provides fault-tolerant propulsion for use as a launch es ...

uses the same storable (non-cryogenic) hypergolic propellant as the small Draco thrusters, but is much larger and delivers over 100 times the thrust. SuperDraco engines are being used on the

Crew Dragon Dragon 2 is a class of partially reusable spacecraft developed and manufactured by American aerospace manufacturer SpaceX, primarily for flights to the International Space Station (ISS). SpaceX has also launched private missions such as Ins ...

spacecraft to provide launch-escape capability in case of a failure in the launch vehicle. Draco and SuperDraco combine the functions of a reaction control system and main propulsive engine.

Draco

Draco thrusters generate 400 newtons (90

pounds-force The pound of force or pound-force (symbol: lbf, sometimes lbf,) is a unit of force used in some systems of measurement, including English Engineering units and the foot–pound–second system. Pound-force should not be confused with pound-ma ...

) of thrust using a

storable propellant A propellant (or propellent) is a mass that is expelled or expanded in such a way as to create a thrust or other motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the e ...

mixture of

monomethyl hydrazine Monomethylhydrazine (mono-methyl hydrazine, MMH) is a highly toxic, volatile hydrazine derivative with the chemical formula . It is used as a rocket propellant in bipropellant rocket engines because it is hypergolic with various oxidizers such as ...

fuel and

nitrogen tetroxide Dinitrogen tetroxide, commonly referred to as nitrogen tetroxide (NTO), and occasionally (usually among ex-USSR/Russia rocket engineers) as amyl, is the chemical compound N2O4. It is a useful reagent in chemical synthesis. It forms an equilibrium ...

oxidizer. The Draco thrust is comparable to the Marquardt R-4D engine developed for the Apollo Service and Lunar Modules in the 1960s and used for apogee/perigee maneuvers, orbit adjustment, and attitude control. Sixteen Draco thrusters are used on the Dragon spacecraft for

attitude control Attitude control is the process of controlling the orientation of an aerospace vehicle with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc. Controlling vehicle ...

and maneuvering.

SuperDraco

On February 1, 2012 SpaceX announced that it had completed the development of a new, more powerful storable-propellant rocket engine, this one called SuperDraco. This high-thrust hypergolic engine—about 200 times larger than the Draco RCS thruster hypergolic engine—offers deep throttling ability and just like the Draco thruster, has multiple restart capability and uses the same shared hypergolic propellants. Its primary purpose is for SpaceX's LAS (launch abort system) on the Dragon spacecraft. According to the NASA press release, the engine has a transient from ignition to full thrust of 100 ms. The development of the engine was partially funded by NASA's CCDev 2 program. SuperDracos are used on both the

and were used on the SpaceX DragonFly, a prototype low-altitude test article that was used for

flight test Flight testing is a branch of aeronautical engineering that develops specialist equipment required for testing aircraft behaviour and systems. Instrumentation systems are developed using proprietary transducers and data acquisition systems. D ...

ing various aspects of the propulsive-landing technology. While the engine is capable of of thrust, during use for DragonFly testing, the engines were planned to be throttled to to maintain vehicle stability. First firing of all 8 Super Draco engines took place on 6 May 2015 at 9am EST at the SpaceX Crew Dragon Pad Abort Test. SuperDraco engines are capable of being restarted many times, and have the capability to deeply reduce their thrust providing precise control during propulsive landing of the Dragon capsule. SpaceX have since announced they will not be using propulsive landing on the Dragon 2. , SuperDraco is the third most powerful engine developed by SpaceX, approximately 200 times more powerful than the Draco RCS thruster engines, and only outmatched by the Raptor and Merlin. In addition to the use of the SuperDraco thrusters for powered-landings on Earth, NASA's Ames Research Center studied the feasibility of a Dragon-derived Mars lander for scientific investigation until 2017. Preliminary analysis indicated that the final deceleration needed would be within the retro-propulsion SuperDraco thruster capabilities.

References

External links

Official SpaceX announcement and test videoMultiple Draco Test Firings
Test firing video of a set of five Draco thrusters for various intervals, SpaceX, 2010-01-27. {{DEFAULTSORT:Draco (Rocket Engine) SpaceX rocket engines Rocket engines using hypergolic propellant Rocket engines using the pressure-fed cycle Rocket engines of the United States

Draco

SuperDraco

See also

References

External links